Baseball, and to a lesser extent softball, is unique in the way in which the ball is pitched to the batter. Almost all other games of any popularity either use a large, soft ball such as basketball, volleyball or football, or a small ball which is struck with a stick or racket like polo or tennis. Baseball and its spinoffs may be unique in that the ball is actually grasped by hand, and an integral part of the play is pitching it at as great a speed as possible, imparting the maximum spin permitted by the skills of the pitcher.
Softball uses the same basic dynamics although the underhanded toss is much slower than baseball. In both cases however, the ball rolls off the fingers as it is propelled from the hand, and it is the way the hand is held which will determine if the pitch is accurate or not. Especially with softball, there is a tendency for the ball to "wobble" to the left or right off of the middle finger at the last instant, in parting it with a slight inaccuracy. Aside from the middle finger wobble, the configuration of the fingers, like almost any sport, has an optimal arrangement, with deviations being less than optimal. Although not a lot of practice time is devoted to configuring the fingers, this is an nevertheless integral part of accurate pitching. The quality of the pitch is dependent on the fingers being held consistently in the optimal position from one pitch to the next.
There is a vast array of training devices that have been invented, and in some cases produced and marketed for almost any aspect of any sport. There are numerous swing training devices for batting practice. However, there is nothing available to assist the baseball or softball pitcher in attaining and holding the correct finger posture for pitching the ball throughout the pitching stroke.